Motor compressor



June 22, 1937. R. PATERAS PESCARA 2,084,823

MOTOR COMPRESSOR Filed Sept. 7, 1935 6 Sheets-Sheet l NTOR INVE RAULPETERAS PESCARA June 22, 1937. R. PATERAS PESCARA 2,034,823

MOTOR coMr RBssoR Filed Sept. 7, 19:55

6 Sheets-Sheet 2 INVENTOR RAUL PETERAS PESCARA QQW June 22, 1937. R.PATERAS PESCARA 2,084,823

MOTOR CQMPRESSOR Filed Sept. 7, 1935 s Sheet-Sheet s F'QYV a? 48%; Q?Uzi 33 361 I r56 INVENTG? RAUL PETERAS PEscAm mmq b ATTORNEYS;

June 22, 1937. PATERAS p sc 2,084,823

MOTOR COMPRESSOR Filed Sept; 7, 1935 s Sheets-Sheet 4 Wig. 14

I NVENTOR RAUL PETERAS PESCARA ATTORNEYS BQQMRQW June 22, 1937. R.PATERAS PESCARA 2,034,823

MOTOR COMPRESSOR iled Sept. 7, 1935 6 SheetS-Sheet-S INVENTOR RAUL.PETERAS ESCARA TTOPNEYI? June 22, 1937. R. PATERAS PESCARA MOTORCOMPRESSOR Filed Sept. 7, 1935 6 Sheets-Sheet 6 INVENTOR RAUL PETERASSCARA ATORNEYS Patented June 22,1937

UNITED STATES,

PATENT. OFFICE MOTOR COMPRESSOR Raul Pateras Pescara, Paris, FranceApplication September 7, 1935, Serial No. 39,643 In Belgium September 7,1934 19 Claims.

The present invention relates to motor-compressors having free pistons,this term designating machines which transform directly the combustionenergy of a liquid, gaseous, or even powdery fuel, into energy stored upin the form of the pressure of a compressed fluid, such as air, withoutthe medium of a mechanical energy, this term including machines workingaccordingto a uniof the movable parts by.-varying the fuel feed,

said means being directly operative by a variable effect, such as thestroke or the acceleration ,of one of the movable parts, or evenindirectly controlled by the pressure of a gas the value of whichdepends upon the stroke of said movable parts.

According to another feature of the present invention, I combine withthe regulating means above referred to, regulating means for varying thepower of the machine and also the time of injection or ignition byvarying the rate of feed of fuel or the feed pressure or both.

*,.Still another feature of the present invention 3.) consists inproviding means for automatically adapting the correction devices abovereferred to to the various conditions of working of the ma.- chine. A

Other features of the present invention will .40 result from thefollowing detailed description of some specific embodiments thereof.

Preferred embodiments of the present invention will be hereinafterdescribed with reference 55 shows, in a'similar mannerg-a portion ofrent from that shown a machine similar to that of Fig. 1, furtherincluding a correcting device combined with the normal regulatingdevice;

Figs. 5, 6 and 7 show, in a similar manner, the distributing elements ofthe machine shown by Fig. 4, in three respective positions differentfrom that illustrated by Fig. 4;

Fig. 8 diagrammatically shows a modification of the arrangement of theregulating elements of the machine shown in Fig. 4, this modificationincluding a system for stopping the machine;

Fig. 9 diagrammatically shows, in vertical section, a portion of a motorgenerator with free pistons including a different correcting devicecombined with the means for regulating the power and varying the time ofinjection of the motor part of the machine, the correcting means beingautomatically adapted to the various conditions of working of themachine through the action of the regulating device of the receivingportion of the machine;

Figs. 10, 11, 12 and 13 show, in a similar manner,

the distributing elements of the machine according to Fig. 9, in fourrespective positions different from that illustrated by Fig. 9;

Fig. 14 diagrammatically shows, in vertical section,'a portion of amotor generator having free pistons coupled in tandem-like fashion,provided with a correcting device operative by variations of theacceleration of the movable parts of the machine;

Fig. 15 diagrammatically shows, in vertical section, a simple motorgenerator with free pistons provided with a correcting device operativeby variations of the stroke of the movable parts oi. the machine;

Fig, 16 shows, in a similar manner, a modification of such a device inthe case of a motor compressor in which the pressure in the compensatingcushions is variable; 1

Fig, 17 shows, in a similar manner, another modification of such adevice, in the case of a simple motor-compressor which is not providedwith a compensating cushion.

It will be assumed, in the following description, that the motorcompressor with free pistons works on a two stroke cycle.

The compressor itself may be of any conventionalor-other type. 'Fbrinstance, each motor unit includes a cylinder i in. which move, inopposite directions, two motor pistons 2, limitingbetween them a motorchamber 3 and each driving one orseveral compressor pistons, which, as amatter of fact may be part of the motor pistons lasshowninrlgs.1,4,9and-14. The

motor chamber is provided, in its middle part,

with an injection device 4 (or an ignition device) 1 and both the motorchambers and the compressor chambers are fitted with suitabledistributing elements.

'The machine may include, as shown in Figs.

I 1 to 14, at least two units coupled in tandem-like stroke of themovable parts. that is to say of the motor pistons and organs associatedtherewith, produces an important variation of the pressure of the motivefluid, which might be detrimental to the good working and resistance ofthe machine.

According to the present invention, the variations in tLJ stroke of themovable parts of thesemachines are limited by proportioning the amountof fuel injected at 4 to the value of said strokes. In order to obtainthis result, the device for adjusting the feed of the injection pump iscontrolled through a relay, for instance a hydraulic one, made andoperated in such manner that, if the pressure in one of the motorcylinders exceeds the normal value, the amount cf fuel injected into theother motor cylinder, for the following stroke, is reduced by the amountnecessary for restoring the normal pressure in the first mentionedcylinder. Inversely, if the pressure in one of the motor cylinders dropsbelow the normal value, the amount of fuel injected into the othercylinder is increased by the amount necessary for restoring the normalpressure in the first cylinder.

This relay itself may be operative by the maximum pressure existing inthe motor cylinders at the end of the compression stroke (Fig. 1), or bycams or the like operatively connected with one of the movable parts(motor pistons) of the machine (Figs. 4 and 9) or again by a free pistoncoacting with a cylinder driven by the movable parts of the machine.

In the embodiment of Fig. 1, the relay consists of an oil pump includinga cylinder 6, a piston 1 and a distributing member or slide valve 8.This pump is adapted to feed an accurately measured amount of oilintended to act on one or the other of the faces of a control piston 9acting on the quantitative adjustment rod II) of the injection pump I Ifrom which injector 4 is fed. This control adjustment may, for example,be of the type shown in Patent No. 1,845,600. This pump H is, forinstance actuated through a cam l3 integral with the movable part I3rigid with the end motor pistons 2.

As shown in Fig. 1, the piston 1 of the oilpump is controlled by anoscillating cam l2, driven by movable part I3 This oil pump draws oilfrom a reservoir M and discharges it, through a check valve l 5, into acylinder IS in which slide valve 8 is movable. Valve 8 is subjected, onthe one hand, to the action of the pressure existing in a chamber H,which communicates, through a valve 18, with one of the motor chambers3, and, on the other hand, to the action of a return spring I9. p

Slide valve 8 is provided with two grooves 20 and 2!. The lowergroove 2!communicates, through a. conduit 22 provided throughout valve 8, withcylinder it. Before cylinder l6, there is provided a conduit 23, with acheck valve Mffor the return of oil to reservoir M. The top of cylacertain position, drive inder I6 is also placed in communication,through conduit 25, with said reservoir l4, for the return of oilthereto. .Cylinder I6 is also provided with two conduits 26 and 21through which oil can be fed to chamber30, which contains piston 9, foracting on one face or the other of said piston.

The position of slide valve 8 depends upon the maximum pressure existingin motor chamber 3. In Fig. l I have shown the position of the slidevalve when said pressure is not sufiicient, which therefore wouldcorrespond to too short a stroke of the driving pistons 2. In this case,slide valve 8 permits oil discharged by pump 6-! to pass through groove20 and conduit 21, which produces an upward displacement of piston 9 anddrives the adjustment rod ll] of the injection pump ll in'the directionof the arrow marked with positive sign this corresponding to an increaseof the feed of fuel for the next injection. The oil discharged by piston9 returns to reservoir I4 through conduits 26 and 25.

In Fig. 2 I have the position of slide valve 8 for a normal stroke ofthe pistons. In this case, slide valve 8 stops both of conduits 26 and21 and the whole of the oil drawn by the pump 6'| is returned to thereservoir through valve 24 and conduit 23. i

In Fig. 3 I have shown the position of slide valve 8 when the pressurein motor chamber 3.

is too high (the stroke of the pistons being too long). In this case,valve 8 permits the flow of oil, discharged by pump B'I, throughgroov'e'2ll and conduit 26, which produces a downward displacement ofpiston 9 and drives the adjustment rod ID of the feed pump II in thedirection of the arrow marked by the negative sign thus reducing thefeed for the next injection. The oil discharged by piston 9 is returnedto reservoir I4 through passages 21, 2|, 22 and 25.

The pressure in chamber l'l', which corresponds to the maximum pressureexisting in the motor chamber 3 at the end of the stroke of the drivingpistons must be eliminated after each motive impulse, and this resultmay be obtained,

for instance, by providing in this chamber H avalve 28 which is openedat .the proper time by a finger 29 operatively connected with cam l2.

The amount of oil that produces the displacement of piston 9 andtherefore ensures the quantitative adjustment of the fuel feed may bemeasured, in a more precise manner, by means of the device shown inFigs. 4 to 7 orof the device of Figs.9to13.

In these embodiments of the-invention, pump B---'! is done away with andthe measuring of the oil introduced intoachamber 30, which is limited bypiston 9, is made by the distributing -element (slide valve) itself,:this, measuringjbeing performed, for instance, inaccordancefwith thelength of the stroke ofthe driving-pistons 2.

In the embodiment of Figs. 4 .to 7, the movable member !3 rigid with the"end driving pistons is provided with two cams 3I and-3P, of suitableoutline. acting on 'tworslide'valve's 32 and 32 Slide valve 32ensuresffor instance the correction correspondingto tooshortstro-kes andslide valve 32 that corresponding to too'long strokes.

Valve 32 moves in a cylinder 33 and can; from return spring 35. j

Into cylinder 33 open two conduits 62 and 13 located at different levelsand both connected a piston 34 urged by a with a conduit 36,.'I'herealso opens into cylinaxial conduit 4| extending through piston34,

with cylinder 33.

In Fig. 5 I have shown the relative positions of the different partsabove described when slide valve 32 in the course of its upwarddisplacement produced by the action of cam 3| is about to shut theopening 42 of conduit 36 through which reservoir l4 communicates withthe inside of cylinder 33, that is to say with the space existing atthis time between slide valve 32 and piston 34, which is applied againstits seat by spring 35. As soon as slide valve 32 has closed this opening42, this communication is cut oil and the amount of oil enclosed in thisspace (between pistons 32 and 34) produces the upward displacement ofpiston 34 until the opening 43 is uncovered (Figs. 4, 6 and 7), in whichposition said piston 34 stops.

During this upward displacement of slide valve 32 and piston 34, one ofthe openings of .conduit 31 is always stopped, either by slide valve 32at the beginning of the displacement (Fig. 5), or by piston 34 at theend of the displacement (Figs. 4 and 6).

The amount 01 oil between slide valve 32 and piston 34 decreases afterthe stopping of said piston 34, due to the opening of opening 43. as theslide valve 32 is moving upwardly and it becomes zero (Fig. 7)(corresponding to the maximum upward stroke of the piston) when thestroke of the movable part I3 (and of cam 3| is normal.

Supposing that. in fact, this stroke is normal. Piston 34 follows, forsome time, slide valve 32 in its upward movement, until piston 34occupies the position shown in Fig. 5', after which valve 32 movesfurther down, uncovering opening42. A new amount of oil. coming fromreservoir 14,, then fills the space inside cylinder 33 between slidevalve 32 and piston 34. This new amount of oil will be wholly d schargedfrom said space in the manner-above described if the next stroke is alsonormal.

\ On the contrary, when the stroke is too short, cam 3| does not liftvalve 32 up to its highest position and a certain amount of oil, whichis the more considerable as the stroke is more insuflicient, remainsstored up in the space between32 and 34. During the upward movement ofslide valve 32 piston 34 first follows the movement of said valve, whichcloses opening'i43 and cuts off the communication with reservoir |4.When the groove 40 of piston 34 reaches the level of the upper opening-of conduit 31, the oil present between members. 32 and 34 can flow intosaid conduit 31 through the axial conduit 4| of said piston 34, and thewhole of said oil is expelled under the action of spring 35, whichimmediately applies piston 34 against its seat, while valve 32keepsimoving in a downward manner, but at a slower rate. The oil thusdischarged escapes through conduit 31, the groove 39 of slide valve 32and conduit 38, toward chamber 30, so as to displace piston which acts(either directly or indirectly) in the direction Y of the arrow markedby positive sign on the adjustment rod ID of the fuel feed pump l I, so

as to increase the feed of fuel injected into cylinder at the nextstroke.

In the case of too long a stroke, cam 3| and distributing member 32 act,for instance, for

- discharging oil from chamber 39, through check valve 44 and conduit33', into reservoir H. For this purpose n'gember 32 the normal upperpoint of which is located at the level of conduit 38 for normal strokes,stops this conduit 33 when the stroke is too long and discharges anamount I employ a single distributing member 32, provided betweenchamber 30 and reservoir l4 and housed in a cylinder 33. Distributingmember 32 is provided with a single circular groove 40, communicating,through axial passage 4| with cylinder 33. Between cylinder 33 andchamber. 30, there are provided two communication conduits, one 38provided with an automatic check valve 46 for the discharge and theother 38 with an v automatic check valve 46 for suction. Betweencylinder 33 and reservoir N, there is established a conduit 36 havingtwo openings 42 and 43 located at difierent levels, conduit 42 beingnoranally closed by a valve 41 acted upon by a spring The distance a(Figs. 9 and 10) between the openings43 and 38 measures the amount ofoil which is, for each upward movement of distributing member 32,discharged into chamber 33 because, in view of the action of spring 48on valve 41, said valve is moved from its seat only after slide valve 32has closed conduit 38 At this time, groove 40 uncovers the inlet ofconduit 38 and distributing member 32, when moving downwardly, drawsfrom chamber 30, through conduits 38, 4| and past valve 46 an amount ofoil proportional to the height. b which corresponds to the lift ofdistributing member 32 above conduit 38 At the end of each downwardstroke, said distributing member uncovers opening 43, thus feedingcylinder 33.

It will be understood that the amount of oil drawn in from chamber 30,depends upon value b. When b is smaller than a (Fig. 11) the amount ofoilthat is drawnin is lower than the constant amount discharged intochamber 30, which corresponds to too short a stroke of movable part I3and piston 9 acts upon the adjustment rod In of the feed pump as in thepreceding examples. When I; is equal to a (Fig. 12 and normal stroke),the amount of oil that is sucked in corresponds to the amount that isdischarged and piston 9 remains stationary. On the conable parts.

For this purpose, I fit on said movable part I3 a cylinder 49 in whichis housed a free piston 50, urged toward its abutment Si by a spring 52.This cylinder 49 contains a liquid and communicates, through at leastone orifice 53, with a chamber 54 into which opens a tube 55 connectedwith chamber 30, in which is housed the piston 9 which controls theadjustment rod ID of the feed pump, in the-direction above stated.

Under the influence of the acceleration of movable part I3 a piston 50is displaced and. drives a portion of the liquid through orifice 53,chamber ,54 and tube 55, into chamber 30, which lifts piston 9 with anamplitude which corresponds to the movement of piston 50. A stationaryreturn tube 56 brings the liquid discharged by piston 9 into a chamber51 which communicates through an orifice 58 with chamber 59, provided incylinder 49 behind the free piston 50. Thispiston includes an axialpassage provided wltha check valve 60, in such manner that the liquidcan flow back to cylinder 49. A calibrated and adjustable small conduit6| makes it possible for the liquid that has acted on piston 9 to beslowly evacuated through the return tube 56. According as theacceleration of the movable part I3 is high or low, the amount of liquidacting on piston 9 is more or less important, in such manner that if theacceleration exceeds its normal value (for instance in the case of toostrong an explosion) rod ID is operated so as to reduce the amount of 1fuel that is injected. On the contrary, for too low an acceleration (forinstance. in the case of an insufiicient explosion) piston moves with astroke smaller than its normal stroke.

It should be well understood that the invention v is in no way limitedto the arrangements of measof stroke on a dial or the like and toprovide means for automatically-stopping the machine when the variationof stroke exceeds the limits of normal running.

Such a device is shown by way of example in Fig. 8. 'In this case, aneedle 62; controlled by piston 9, indicates on a dial 63 the variationsof The injection of fuel can be stopped,

stroke. when these variations exceed the limit that have been fixed, bythe pressure of a fluid, fed from a source not shown on the drawings, ona piston 64 which acts on a rocking lever 65 as soon as a slide valve66, rigid with piston 9, allows said fluid to flow into conduit 61,which leads said fluid to piston 64.

Also according to the invention, the correction. of the strokes by thequantitative adjustment of the fuel injection may be combined with theregulation of the power of the machine, generally obtained by thequantitative variation of the fuel injected. I

For this purpose, and as shown by Figs. 4, 8 and 9, this automaticregulation is obtained by bringing into play the pressure existing inthe reservoir 68 into which the compressors discharge their fluid underpressure. This pressure is transmitted through a conduit 69 to a piston10 acting, through a cam I I, for instance an oscillating cam, and anequalizer bar 12, on the rod III which controls the quantitativeadjustment of the feedpump ll. Advantageously, the device for correctingthe strokes of the pistons is combined with the regulating device, forinstance by causing the rod E3 of the correcting piston 9 of the dosingrelay to act on the equalizer bar 12.

I may also, according to the invention, combine with the device forregulating the power and with the device for correcting the values ofthe strokes, the variation of the point of injection or ignition, byinterposing, for instance, as shown by Fig. 9,

between the control cam I3 and the push member of the injection pump H,a lever 14 which bears upon the cam l3 and the other end of which ispivotally connected to an oscillating member 15, connected through a rod76 with the regulating piston 10. It is thus possible to adapt theposition of the point of injection to the value of the stroke, whichdepends upon the discharge pressure of the machine, the strokes beingshorter when the pressure is higher.

device for correcting the strokes may be adjusted to the variousconditions of load of the machine, as well when the variations of loadare obtained by'varying the pressure as when they are obtained byvarying the output, or again by varying simultaneously both of thesefactors.

For this purpose, I may, as shown by way of example in Fig. 9, interposebetween cam 3| and the distributing piston 32 of the relay which iscontrolled by said cam an intermediate lever 18 pivotally connected toan oscillating member H, which can be moved, both laterally andangularly. Thelateral displacement is for -instance produced by a rod 19which may be coupled to the regulator of the receiving machine while theangular displacements of said lever 11 are obtained in consequence ofthe displacements of a rod 16 responsive to variations of the dischargepressure, for instance by operatively connecting said rod 16 to thepiston 10 above referred to. Besides, rod 16 may advantageously, asshown in Fig. 9, simultaneously control the variation of the point ofinjection,'as above explained.

Although the principle of the invention is especially applicable tomachines of the kind in question which are associated in tandemarrangement, this principle may also be applied to simple machines ofthis type, and more especially to those which must work for a long timeunder the same conditions of load.

In these simple machines, the amount of fuel injected into the cylindermay be varied. In the embodiment of Fig. 15, this variation is obtaineddirectly. in accordance with the value of the stroke of movable memberI3 In the embodiments of Figs. 16 and 1'7, the variation of the fuelfeed is obtained in accordance with the pressure existing in auxiliarychambers, such for instance as the compensation reservoir or cushion 80,the

pressures in these chambers depending upon the Furthermore, according tothe invention, the

stroke of the movable parts of the machine, or a in accordance withtheacceleration of said movable parts, or in any other way.

As in the preceding examples illustrated by the drawings, the adjustmentrod l0 ofthe feed pump ll of the motor is acted upon by a control pistonupward movement of the valve being obtained through a cam 3 loperatively connected with said movable part I3 (Fig. 15).

In the embodiment of Fig. 16, this upward movement of member 8 isobtained through the action of the maximum pressure existing in the thispressure being transmitted directly to distributing valve 8, through aconduit 88.

In the case of Fig. 15, the upward movement of distributing valve 8 isthe greater as the stroke of the, movable part I3 is longer. Besides,the operation of this device is analogous to that ex- I plained withreference to Fig. 1. The distributing valve 8 may be kept in position,during the non-motive stroke of the driving pistons 2, for instance bymeansof a pawl such as 83, urged by a spring 84 and released by theaction of a finger 85 mounted on the movable part I3 near the end of thenon-motive stroke of said pistons 2.

In the case of Fig. 16, the distributing valve is lifted near the end ofthe motive stroke, by the pressure existing in the compression cushion80 and this pressure keeps acting, owing to the check valve 86, duringthe non-motive stroke of piston 2 until said piston uncovers an orifice81, near the end of said nonmotive stroke, which'oriflce opens into saidcompensation cushion 80. In this case also the working of the dosingrelay is analogous to that above described with reference to Fig. 1. v

Fig. 17 shows a modification of the preceding arrangement in which theauxiliary chamber 8!, with its check valve 86, plays the same part ofthe compensating cushion 80. I

Anyway, for given conditions-of working, any variation of the stroke ofthe movable part, or of the maximum pressure existing in chamber 68, 80or 8|, automatically produces an inverse variation of the amount of fuelthat isiniected to the machine, in such manner as to stabilize theworking conditions and therefore the output of the machine.

In this case also the correction of the amount of fuel injected into themachine may be adapted to the various conditions of loading of themachine and this for a hand control or for an automatic control.

In Fig. 15 I have shown, by way of example, a control from adistance 89acting upon a sleeve 90 which, due to its sliding movement betweendistributing valve 8 and connecting conduits 26 and 21, makes itpossible to advance or delay the distribution of fluid to the faces ofpiston 9, and therefore to adapt the correction to various conditions ofloading. This control member 89 may I be operated manually or it may becoupled with a governor, in which case it becomes automatic.

In the embodiments of Figs. 16 and 1'7, I have disclosed means foreffecting an automatic cor-a rection in accordance with the pressureexisting in the'reservoir 68 of the machine.

In this case, the compensating cushion (Fig. 16) or the auxil-' iarychamber 8| (Fig. 1'7) is connected, at the end of every inward stroke ofthe driving pistons 2,

and eflicient embodiments of the present invention, it should be wellunderstood that I do not wish to/jbe'limited thereto as there might bechanges made in the arrangement; disposition and form of the partswithout departing from the principle of the present invention ascomprehended within the scope of the appended claims.

What I claim is:

1. A motor compressor of the type described, having motor andcompression cylinders, and pistons freely slidable in said cylinders,which comprises, in combination, means for feeding fuelto said motorcylinders, fuel feed adjusting means for varying the amount of fuel fedby said means at each stroke, and means, responsive to variations in theworking strokes of said pistons, for controlling said adjusting means soas toregulate the working of the motor compressor.

2. A motor compressor of the type described which comprises, incombination, at least one cylinder, two driving pistons freely movablein said cylinder, fluid compressing means directly operative by saidpistons, means for feeding fuel into said cylinder between said pistons,fuel feed adjusting means for varying the amount of fuel delivered bysaid fuel feed means at each stroke, and means responsive to variationsof the stroke of said pistons for controlling said adjusting means.

3. A motor compressor of the type described which comprises, incombination, at least one cylinder, two driving pistons movable in saidcylinder, fluid compressing means directly operative by said pistons,means for feeding fuel into said cylinder between said pistons, fuelfeed adjusting means for varying the amount of fuel delivered by saidfuel feed means at each stroke, a chamber, means for producing in saidchamber a fluid pressure corresponding to the value of the stroke ofsaid pistons, and means responsive to variations of said fluid pressurefor controlling said fuel feed adjusting means. I

4. A motor compressor of the type described which comprises, incombination, at least one cylinder, two driving pistons movable in saidcylinder, fluid compressing means directly operative by said pistons,means for feeding fuel into said cylinder between said pistons, fuelfeed adjusting means for varying the amount of fuel delivered by saidfuel feed means at each stroke, a reservoir of liquid, a pump for-saidliquid fed from said reservoir and operative by said pistons, acylinder, a piston movable in said cylinder, means operative by saidlast mentioned piston for controlling said fuel feed adjusting means, apassage connecting the discharge of said pump with the part of said lastmentioned cylinder on one side of said last mentioned piston, a passageconnecting the discharge of said pump with the part of said lastmentioned cylinder on the other side of said last mentioned piston, achamber contributing valve operative by the fluid pressure in saidchamber, capable of stopping at least one of said passages.

5. A machine according to claim d including two motor cylinders, eachwith two driving pistons disposed in tandem relation, the chamber abovementioned consisting of the space between the driving pistons of one ofsaid two driving cylinders, acting in combination with the fuelinjecting means of the other motor cylinder.

' nected to said compressing means, and a dis-' 6. A machine accordingto claim 4 in which said chamber consists of the compensating cushbysaid pistons, means for feeding fuel into said cylinder between saidpistons, fuel feed adjusting means for varying the amount of fueldelivered by said fuel feed means at each stroke, a cylinder, a pistonmovable in saidcylinder, means operative by said last mentioned pistonfor controlling said fuel feed adjusting means, a reservoir for aliquid, means responsive to decreases of the strokes of said pistonsbelow the normal value of said stroke for discharging liquid from saidreservoir into said last mentioned cylinder so as to move said lastmentioned piston in the direction that corresponds to an increase of thefuel feed,

and means responsive to increases of the strokes move said lastmentioned piston in the oppositev direction, Y

9.'A motor compressor of the type described which comprises, incombination, at least one cylinder, two driving pistons movable in saidcylinder, fluid compressing means directly operative by said pistons,means for feeding fuel into said cylinder between said pistons, fuelfeed adjusting means for varying the amount of fuel delivered by saidfuel feed means at each stroke, a cylinder, a piston movable in saidcylinder, means operative by said last mentioned piston for controllingsaid fuel feed adjusting means, a reservoir for a liquid, a cylindricalsleeve, two slide .valve elements movable in said sleeve, passages,extending through said sleeve and including a portion of thepyiindricalbore thereof, connecting said reservoir with the part of the lastmentioned cylinder located on one side of the last mentioned piston,said side being that on which an increase of pressure shall move saidlast mentioned piston in the direction that corresponds to an increaseof the fuel feed, means operative by said first mentioned pistons forimparting to oneof said slide valve elements a reciprocating movement ofan amplitude proportional to the stroke of said first mentioned pistons,an abutment for the other side valve element limiting the displacementsof said second mentioned slide valve element toward the other slidevalve element, spring means for applying said second mentioned slidevalve element against saidabutment, said passages opening into saidcylindrical bore of the sleeve at points such that a decrease of thestroke of the two first mentioned pistons below the normal value of saidstroke causes liquid to be discharged from said reservoir into thesecond mentioned cylinder through said passage, and liquid pumpingmeans, associated with said passage and operative by said drivingpistons v with a stroke proportional to the stroke of said 4 drivingpistons for drawing liquid from said part said cylinder between saidpistons, fuel feed adjusting means for varying the amount of fueldelivered by said fuel feed means at each stroke,

a cylinder, a piston movable in said cylinder, means operative by saidlast mentioned piston for controlling said fuel feed adjusting means, areservoir for a liquid, a cylindrical sleeve, a slide valve movable insaid sleeve, two passages, extending through said-sleeve and including aportion of the cylindrical bore therein, interconnecting said reservoirand the part of the last mentioned cylinder located on one side of thelast mentioned piston, said side being that on which an increase ofpressure shall move said last mentioned piston in the direction thatcorresponds to an-increase of the fuel feed,'valve means in said twopassages arranged in such manner that one of said passages permits onlythe flow of liquid from the reservoir to the last mentioned cylinder andthe other passage permits only the flow of liquid from said lastmentioned cylinder to said reservoir, means operative by said drivingpistons for imparting to said slide valve element a reciprocatingmovement of an amplitude proportional to the stroke of said drivingpistons, said passages opening into the cylindrical bore of said sleeveat points such that each alternating movement of said slide valvecorresponds to a discharge of a constant amount of liquid from saidreservoir into said cylinder, and to the return, from said lastmentioned cylinder into said.

reservoir, of a certain amount of liquid depending upon the stroke ofthe driving cylinders.

11. A motor compressor of thetype described which comprises, incombination, at least one cylinder, two driving pistons movable in saidcylinder, fluid compressing means directly operative by said pistons,means for feeding fuel into said cylinder between said pistons, fuelfeed adjusting means for varying the amount of fuel delivered by saidfuel feed means at each stroke, a reservoir of liquid, a pump for saidliquid fed from said reservoir and operative by said pistons, acylinder, a piston movable in said cylinder, means operative by saidlastmentioned piston for controlling said fuelfeed adjusting means, apassage connecting the discharge of said pump with the part of said lastmentioned cylinder located on one side of said last mentioned piston, apassage connecting the discharge of said pump with the part of said lastmentioned cylinder located on the other side'of said last mentionedpiston, a distributing valve capable of stopping at least one of saidpassages, and means operative by said driving piston for fixing theposition of said valve in accordance with the value of the stroke ofsaid pistons.

12. A motor compressor of the type described which comprises, incombination, at least one cylinder, two driving pistons movable in saidcylinder, fluid compressing means operative directly-by said pistons,means for feeding fuel into said cylinder between said pistons, fuelfeed adjusting means for varying the amount of fuel delivered by saidfuel feed means at each stroke, and means responsive to variations ofthe acceleration of said driving pistons for controlling said adjustin'gmeans. 1

13. A motor compressor of the type described, which comprises, incombination, at least one cylinder, two driving pistons movable in saidcylinder, fluid compressing means operative directly by said pistons,means for'feeding fuel into said cylinder between said pistons, fuelfeed adiusting means for varying the amount of fuel 75 delivered by saidfuel feed means at each stroke,

. a cylinder, a piston movable in said cylinder,

means operative by said last mentioned piston for controlling said fuelfeed adjusting means, a cylinder rigidly connected with one of saiddriving pistons, an abutment in said lastmentioned cylinder, a pistonmovable freely in said-last mentioned cylinder, spring means forapplying said last mentioned piston against said abutment, and a systemof passages and conduits connecting respectively corresponding sides ofthe two last mentioned cylinders with one another, whereby a variationin the acceleration of said last mentioned piston can produce a movementof the above mentioned piston in its cylinder.

14. A machine according to claim 2 further including means operativelyconnected with the last means ofclaim 2 for indicating the value of thestroke of said driving pistons.

15. A machine according to claim 2 further including means operativelyconnected with the last means of claim 2 for stopping the machine whenthe strokes of the driving pistons vary beyond certain limits.

16. A machine according to claim 2 further including means, responsivemeans responsive to variations of the load of the machine forinfluencing said fuel feed adjusting means.

17. A machine according to claim 2 further including a reservoir for thefluid under pressure fed by said fluid compressing means, and meansoperative by the fluid pressure in said reservoir for varying theactionof said fuel feed adjusting means.

18. A machine according to claim 2 further including a reservoir for thefiuid under pressure fed by said fluid compressing means, and meansoperative by the fluid pressure in said reservoir for varying the timeof injection of fuel into said cylinder.

19. A machine according to claim 2 further including a reservoir for thefluid under pressure fed by said fluid compressing means, meansoperative by the fluid pressure in said reservoir for varying the actionof said fuel feed adjusting means in accordance with said fluidpressure, and means operative by the fluid pressure in said reservoirfor varying the time of injection of fuel into said cylinder inaccordance with the value of said fluid pressure.

RAUL PATERAS PESCARA.

